Input buffers reside in many electrical devices such as memory devices and processors to receive input signals. The input signals may represent data. In some devices, the value of the data is determined by the voltage difference between voltage levels of the input signals. The input buffers detect the voltage difference and generate an output signal that reflects the value of the data.
Most conventional input buffers are designed to operate at some specified values for operating parameters such as supply voltage range, process variations, temperature range, input signal voltage swing, and input signal slew rate.
Changes in one or more of the operating parameters, for example a lower supply voltage and a smaller input signal swing, may cause some of the conventional input buffers to generate the output signal with poor symmetry between rising and falling signal transitions. Changes in the operating parameters may also cause some conventional input buffers to stop function.